Evidence suggests that we are at the onset of another sea
star wasting event. Sea stars on both the east and west coasts of the United
States have fallen victim to a wasting disease that overcomes the Pisaster
ochraceus in a matter of days once an initial lesion appears. The disease, while
currently not understood, is rapidly transmitted amongst the population once it
takes hold. On the west coast studies show that the disease is bacterial but on
the east coast it is viral. Both result
in a similar disintegration of the flesh within a very short period of time.

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Sea Star Wasting Syndrome has been documented for the last
three decades by research teams from the University of California, Santa Cruz
Pacific Rocky Intertidal Monitoring Program. Scientists have suspected warmer
than normal temperatures associated with climate change to be a potential cause.
Wasting events have been documented in the past, in particular, one event
dating back to 1983-84 in Southern California and a second, albeit smaller event,
between 1997-98. West coast monitoring has been done at more than 200 sites
from Southeast Alaska to Mexico. Additional studies have been done on the east
coast off the coast of Maine.

Rocky
intertidal habitats occur on the shores at the interface between the
terrestrial and marine environments. This unique location results in a physical
complexity that leads to high biological diversity, including many species that
are found only in this narrow band of coastal environment. Rocky shores are
also the most accessible marine habitat, which fosters a strong public
appreciation of these communities, but also makes them vulnerable to
degradation resulting from human activities. Natural temporal variation in
rocky intertidal systems can be quite high, and can occur on the scale of
months (seasonal), years, and even decades, so long-term monitoring is
essential for separating natural change from human-induced.

The
brightly colored Pisaster ochraceus sea star subsists on barnacles, snails,
limpets and chitons and can live for up to 20 years. Population recovery after
a wasting event is apparently due to cooler-water conditions and large
recruitment events, which have been documented in many, but not all areas. The
wasting events have been recorded as far north as British Columbia. The ongoing
monitoring project includes an interactive map documenting the location and
severity of the outbreaks.